Kosmetisch – translates into cosmetic, it is referring to the range of filters being used to alter the light in the elevators. These color gels in different shades make nice skintones, except for the green one. For the installation, two elevators have been changed to a greenish color (on the north side of the building), two have been changed to a warm red tone (on the south side).
Eingriff – this german word translates both into intervention and surgery. Not given this context, people might expect to see something related to cosmetic surgery.